Underreamer.



l. LORENZ.

UNDERREANIER.

- APPLlcATloN mso MAY4.1914.

lNVENTOR,

2 SHEETS-SHEET 1.

Patented Apr. 20, 1915.

ATTO R N EY I. LORENZ. UNDERREAMER.

4 APPLICATION FILED MAY 4|. 1914. LlSGZ-B. l Patented Ap1x20, 19K.

2 SHEAETS-SHBET Z.

wlTNEssEs 4 V .V ATTORNEY ImiTED STATES4 PATENT oFFicE.

JOSEPH LORENZ, OF ROBINSON, ILLINOIS.

UNDERREAMER.

To all whom ift-may coa-ern 'Be it `known that.` I, JOSEPH Loniixz, a citizen ofl the United States, residing at Robinson, in the county of Crawford and State of Illinois, have invented a new and useful Underreameigof which the followingis av specification.

This `invention has reference to improvementsin underreamers, and its object is to provide an underreamer' which may be introduced through a sma-ll casing to'drill the bore larger below the casing, so as to iet the casingdown vas rapidly as the rear'ner enlarges the hole, and without interference with either the casing or the underreamer.

The underreamer of the present invention comprises an elongated body member car- "rying at the active end pivoted bits an wedge-like members for throwing the bits readily outward to the requisite distance to 'ream out a hole toA a larger diameter than the casing for permitting the lowering of the latter. The spreading movement imparted to the bits is due to the action of a spring contained within the body member and con-y trolling an elongated slide also within the body member and carrying the actuating lWedges for the bits, while dogs are provided at opposite sides of the bodyfmember in pojected to thereby release the bits to approach sition to hold the bit-actuating wedges prowhile the underreamer is being moved through the casing.I Thei dogs have a normal tendency to move to a released'psition permitting the spring to act, and are so arranged as to move longitudinally .of ,the

body' member for a limited distance, but may be locked at either extreme of their travel .lengthwise of the body member.

rlhe invention will be best understood from I'a considerationv of the following de.

' tailed description, taken in connection with changed and modified so long as such l In thedl-awingsEr-f-Figure 1 is an elevation;

changes vaiidmodilic'ations mark no material departure from the salient features Vof the invention.

Specification of Letters Patent.

- Application led May 1914. Serial No. 836,257.

of the underreamer .within the casing, and the lattershown in diametric cross-section. Fig. 2 is a longitudinal diametric section of the underreamer at right angles ,to the showing of Fig. 1, with some parts shown in elevation and the underreamer shown j\,projected from the end of the. ,casingf\.,l Fig. 3 is a section similar to that ,of F ig`."`2 with the underreamer inside of tlle cas-ing. fFig. 4 is an elevation of the underreamer within the easing and with the latter in section, the view being taken at right angles to that of Fig. 1. Fig. 5 is a section en the line -'of Fig. 2. Fig. 6 is a section on the line 6 6 ofA Fig. 1. Fig. 7 is a section on the line 7-7 of Fig. 1. Fig. 8 is-a section on the line 8 8 of Fig. 1. Fig. 9 is a section on the line 9-9 of Fig. 1. Fig. 10 is a perspective view of certain parts mounted in the body member, some in fixed relation thereto and others slidable lengthwise thereof. Fig. 11 is a per s pective view of a latch dogforxning part of the structure. Fig. 12 is a perspective view of a trigger coacting with the latch dog of Fig. 11. Fig. 13 vis a perspective view of Aone of the reaming bits. Fig. 14 is a. perspective view of a key for holdlng the reaming-bits in place.

`Referring to the drawings, there is shown a v-v'casing 1 such as is customarily used in deep wells, or deep borngs, and it is also customary to employ in conjunction with such casings a structure 'called an ilnderi'eamercapable. of enlarging the bore beneath theA casing, so that the latter may bedriven deeper into the ground.

The underreamer has a body portion 2 lprovided with a longitudinal, axial bore 3 continuedv throughout ,the Vgreater portion of the length from one end where the bore lis th1ea`ded,as indicated at 4, for .the reception of a screw plug 5 formed on the corresponding' end of a drill rod. 6 allin the customary manner. The body" member 2'and ldrill, rod 6 are provided with exterior {iats 7 and v8, respectively, for the application of tools, whereby the body member 2 is s crewed'tight on to the drill rod 6, as is cusl` t0mary. 1 Y

The bore 3 stopsshort of the end ofthe body member 2. remotefrom the 'drill' rod at a web 9, through which there is a centralv sof passage 10, this passage being V- preferably vlatter being-formedwith a longitudinal slot 13 extending from the passage l0 toward its outer end for an appropriate'distance. On opposite sides of each slot the walls thereof are formed with inturned shoulders 14, each having one end" 15 next to the closed endof the recess substantially perpendicular tothe` bottom of the recess, while the other end 16 is inclined outwardly, so 'that the shoulder is substantially there undercut.' v

Since the underreamer in operation is' usually upright with the drill rod 6 -fast to its upper end, expressions" of position found hereinafter have reference to the normal operative position of the underreamer, so that the end of the body member to which the drill rod -is attached may be termed the upper end, while that provided with the recesses 11 and central web 12 may be termed the lower end. The upper end of eac'h recess 11 terminates in a shoulder 17 carrying spaced pins 18, while lodged in each recess is a reamer bit 19 having recesses 20 on opposite sides conforming generally in l shape to the shoulders 14, but with the re- -lcesses of somewhat greater length than the shoulders, oneend 21 of each recess being slightly inclined toward the corresponding or upperl end of the reamer-bit, while thev 4'other end of the recess is formed into an 1nclned shoulder 22 of nearly the s 'ame'incli- 'nation as the shoulder 16,

That end of the reaming bit which may be termed the upper' end and'close to the shoulders 21 is formed with spaced sockets -23 for Lthe reception of the pins 13, while the other or lower end 24 of the blt is appropriately shaped for cutting, the outer face of the bit being iconvex on an arc substantially that of the casing to produce la cut conforming generally to the contour of fthe casing.

The web 12 in line with the shoulders 15 is, provided with passages for4 keys 25, onev of which is lshown separately in Fig. 14. These keys reach to the surface of the body of the reamer, and are appropriately curved or beveled in conformity with the cylindrical shape of the body, and on one long face about midway of its length each key is provided with a notch 26 for a locking pin 27 which may-be in the'form of a screw or be otherwise shaped, and these pins 27 arelntroduced into the body of the reamer from opposite sides thereof, so as to' enter the notches 26, and cape after being once placed 1n position. The ke s 25 are ofsuch width as to approxi- ;.anauv au um man between the shoulders thus hold the keys from es- A 15 and 21, and the shoulders 21 may be slightly rounded to permit a limited rocking movement of the reamer bit without interference fromgthekeys 25, while the pins 18 and sockets 23 are suitably ,related to permit such limited rocking movement.

The body 2 within that portion provided with the bore 3 is formed'with longitudinal slots 28 ondiametrically opposite sides, both slots opening on their inner sides into the bore 3, and each slot having in its opposite walls a longitudinally spaced series of matching. notches 29, the slots and. notches being for a purpose to be described.

Mounted in the bore 3 is a block.30, and since the bore 3 is customarily cylindrical, the block 30,'is likewise cylindrical. At one end the block is provided with an axial stem tion conforming to the passage 10 and for a portion of its length .the stem is recessed 'at the sides, as shown at 32, to receive tongues 33 on the corresponding ends of other stems 344 `carrying vat the ends remote from the stems wedge blocks or -heads 35, each terminatingat the free end in a 4beveled portion 36, the bevels of the beveled ends of the heads 35 being onetoward the other. Each head Where joining thejste'm 34 approaches the stem at an-angle forming a bevel 37. The stems 34 arey for a portion of their length narrower than. the heads 35, thus forming'shoulders 38. The narrow portions of the stems 34`lare of a width to slide freely between theshoulders 14, and the heads 35 arev of a width to .slidefreely in the Wider lower portions of the recesses 11, while the tongues 33 are of the same width as the stem 31 where they are secured to it, the securing means in the 4resent instance being shown as screws' 39. he extreme lower end of the stem 31 is provided with oppositely directed lugs 40 entering slots 41 through the stems 34 near where the tongues 33pmject therefrom. The lugs ,40 coact with the screws 39 to hold the wedge-likeheads 35 to the stem 31v and the slots 41 may be slightly wider than the lugs 40 to permit a very limited side play, so that the Aparts freadily conform to any irregularities which may exist between the bore 3 and the frethe 4heads 35 may travel, and in, which the reamer bits are lodged, so as to rock in part into and outof these recesses or channels. It will also be understood that the lugs 40 may fit snugly in the recesses 41. The purpose of making the heads 35 separate from the stem 31 is to permit assembling of the parts.

cesses 11 constituting channels alongxwhich `Projecting from ythat end of the block 30 I remote ,from the stem 31 are two elongated guide ingers 42 emerging from diametrically opposite 'sides of the corresponding end Aof the block 30 and from an intermediate shoulders 51 approaching the center line of .point each finger'isof lessened thickness, as

indlcated at 43. Each-finger is-pierced near 'thefree end by aperforation 44. 'i i Adapted to the fingers is a cap' disk 45 suitably recessed on opposite sides, as shown at 46, and {When the cap disk is lapplied to the fingers itis held thereto by a staple 47. Applied'tothe fingers 42v is anotherblock 48 having vdiametiically opposite longitudinal grooves 49 in'which the fingers yare seated, and along whichI theymay be moved,

while Von diametrical'ly opposite sides of the block 48 on adiameter substantially at right angles to tthegroo'ves 49 are hollow longitudinal recesses 50 terminating in inclined the block from opposite sides. thereof, and -from .these shoulders lthe block is formed With'widened' surfaces 52 in turn terminat- `ing in other. inclined shoulders 53 directed toward the center line of the block and endy :mgm a Wedge shaped Itongue 54. The {iat-v tenedsurfac'es 52are closer to a longitudinal diametric plane intemediate of and coincid- 25,

ing with the grooves. 49 than lare the bottoms 'ofthe recesses '50, W i ile the tongue 54 `has its sides merging at such diametric plane.

35' firmly against movement in the body 2 and The block 48'vclose to the end remotefrom the tongue 54' is pierced by a passage 55 per- 30- pendicular tothe diametric plane coinciding with the grooves 49 and extending through thispassage is'a pin 56 lodged in an appro- -priate portion of the body 2 and closer to the -end carrying the drill rod 6 than are .the slots 28. The pin 56 holds the block 48 Said block constitutes an abutment for a helical spring 57 surrounding the extension `43 of the l'ingers 42 between the disk 45 and the block 4 8, the tendency of the spring be.,- ing, therefore, "to hold the disk 45 as iar away from/the .block 48 as is permittedv by the engagement of other parts.

Adapted to the surfaces'O and 52 of the v'block' 48'A are elongated triggers 58, one of which is shown separately in Fig. 12. 'The trigger has at one' end 'a right-angular eX- tens1on59 vWith its outer end beveled as shown' at 60. For about half the length of lthe trigger at' the end remote from the eX- tension 59 the thickness of the trigger is fits).

reduced as shown at'6l, and the thin portion and thicker portion are joined by a beveled. shoulder 62, while the extreme end ofthe reduced portion 6l is beveled as vshown at That long side of the trigger from which 'the extension 59 projects lis lop@ .positely inclined, or prismatic, as indicated at-64. Thereare two'triggers'58 withthe stepped surface remote from the triangular or beveled surfacev 64 adapted to the surthe' right-angular extensions -59 project. op-

faces 56 and 52,'While the shoulders 62 and 63 are adapted toY theiiiclined portions'l and. 54 of the 101001648." #When so applied 'andr the s positely onefrom/the/,ether into and through the slots 2.8, the eXttti'siens-'Q having their; beveled ends terminating at about thea surface of the body member 2. i

Lodged ineach slot 28 is a. latch dog 65,*

one of which is shown separately in Fig. l1l. Each dog is in the form of an elongated block of athiclrness to lit snugly, yet freely latch dog is traversed by pins69adapted to the recesses 290i the respective slots 28, this spacing of thepins being the same 'as the spacing of the notches 29,"but` While each dog is provided with two spacedpins each slot 2S has'three vcorrespondingly spaced notches 29.

, The block 48 acts vas'l av wedge-like spreader for vthe triggers 58 alongwhich latter the latch dogs 'are movable lengthwise of the reamer body. .v 4

Then the parts are all assembled, and

vthe reamer is introduced intov the casing-1,

the various structures are related asshown in Fig; 3. lThe triggers have their angle extensions 59 in engagement with those ends of' the slots 28 remote from the drill rod ,6. At the same/time the latchdogs 65 are /lod'g'ed at what lmay be termed the up? per ends of the. slots 28; that is, the ends toward the rod 6.`

end from which the ingers 42 project in abutment with the projections 59 of the triggers 58. In this position of the parts the block 48 -is suiiiciently distant from the block 30 to permit the thicker portions of the triggers to lodge between the beveled tongue 54 and the block 30. with the' inner portions ofthe trighgers resting upon the surfaces 52 the shoulders 53 and tongue 54. The spring 57 is under these circumstances compressed as shown in Fig. 8,Whi1e the latch dogs 65 are approached onetoward the other until Under these circumstances the block BOhas been moved along` the bore 3 until close to the Web 9 with the ..85 While at appropriately spaced points the oulders 62 in engagement lWith their outer 'edges are aboutI coincident with the surface of the reainer4 body .and the pins 69 are seated in the corresponding recesses 429. The tendency o*l the compressed spring 5 7 is to'move the block 30 and parts carried therebyf'toward the end ot vthe .body

2 remote froni'the reamer bits, but this is resisted .by the latch dogswhich atjythe ,time

have their pins 69 seated in the notches 29, and consequently these dogs hold the triggers 58 from movement either longitudinally of the body member or laterally away 5 one from the other, and the triggers in turn hold the block 30 against movement under the action of the spring 57. With the parts in the position described the beveled heads 35 are projected beyond the cutting end of the reamer and consequently are out of the path of the reaming bits 19, so that the latter are readily swung on their hinge pins 18 one toward the other until the spread of these bits is so greatly reduced that they may be introduced within the casing 1. When within the casing the latch dogs 65 'have no room to' move one away from the other to carry the pins 69 out of the notches 29, and consequently the locked condition of 20 the reamer continues.

The reamer is lowered until the latch dogs move beyond the lower edge of the casmg 1, whereupon the latch dogs are readily moved outwardly because they do not resist any more a` spreading movement of the triggers and the latter therefore yield to the action of the spring 57 to move both longitudinally and laterally :forcing the pins 69 of the dogs 65 out of the recesses 29. The longitudinal movement of the block 30 `and parts carried thereby causes the.

heads to'enter between the reaming bits and expand them into operative position;

When f the ,underreamer is to be with- 35 drawn it is lifted until the bottom edge of the casing engages the beveled shoulders 68 of the latch dogs, thus holding these latch dogs while the reamerl continues the upward movement and the latch dogs ultimately reach the lower ends of the slots 28, whereupon being constrained to move with the rising 'reamer the reaction of the lower edge of the casing against the beveledends' 68 causes the latch dogs to approach one toward the other, and ultimately yseat in .the corresponding recesses 29. In the4 meantime the continued upward movement of the reamerhas not been` participated in bythe triggers 58, nor by the block 30, so the spring 57 is compressed. by the block 48 fast to the body of the reamer and the bits 19 are 'moved away from the beveled heads 35, 'so that they may readily approach one toward the other to enter the casing l. ,Whatl is claimed is 1. In an underreamer, an elongatedA body* member, reamer bitscarried thereby, bit expanding means in and movable longitudinally yof the body member in opposite di- 80 rections, a spring constraining the bit expanding means jto move 'inf the active direction, triggers movable with the bit expanding means and also laterally thereto, the ltrigger and bit expanding means having 5 coacting vportions for *causing the lateral 'ing means to move in the active direction,

and longitudinally movable dogs carried by -the body member, said dogs coacting with the bit expanding means and the dogs and body member having1 coacting'locking means for positively holding the dogs at either limit of their travel to in'turn lock the bit expanding means -in theinactive position in opposition to the normal tendency of the. spring. 3. In an underreamer, an elongated body member, reamer bits carried thereby, vbit expanding means in and movable longitudinally of the body member in' opposite directions, and longitudinally movable dogs carried'by ythe body member for locking the bit expanding means inthe inactive position at either limit of longitudinal travel of the dogs, said dogs and body member having coacting means for positively locking the dogs at the opposite limits of their travel in the body member. 4 i

-1.In an underreamer, an elongated body member, reamer bits carried thereby, bit expanding means in and movable longitudinally of the body memberin opposite directions, and longitudinally movable dogs carried by the body member for locking the bit expanding means in the inactive position at either limit oi' longitudinal 4travel of the dogs, said dogs and body member having coacting means for positively locking the dogs at the opposite limits of their travel `in the body member, andv said dogs being movable bodilyin directions laterally to their longitudinal travel and having portions exposed at the surface of the body member.

5, In an underreamer, an elongated body mem-ber with intermediate longitudinal slots von opposlte sides, vreamer bits mounted on the 4body vmember, bit expanding means within the body member and movable longitudinallythereof, and locking dogs mounted in the body member and projecting through and movable longitudinally of the slots for'l locking the bit expanding means in the in-VV active position at either limit of travel of the dogs in the slots, said dogs being'also movable laterally o the body.4 member, and saiddogs andbody member having coactive means for positivelyv locking the dogs against longitudinal movement at -either limitiof theirolongitudinal movement in the asv the body member, bit expanding means- Within the ,body member and mit able longiti `ldinally' thereof, and locking do smounted iihebodymember and projecting throu h a movable longitudinally of the slots or loclring the bit expanding means in the inactive position at either limit 4of travel or the dogs in the'` slots, said dogs 'being also 'movable laterally o f the body member, and

said dogsandbody member having coactive means for positively7 locking the dogs against longitudinal movement at either' limit of their longitudinal movement in th'e slots, said locking means consisting. of projecting pinspn the dogs and spaced recesses in the iva-llt of' the slots.-

- 7.l In an underreamer, an elongated body member with intermediate longitudinal slots onopposite sides, reamer bits mounted on the body. member, bit expanding means Within the body member and movable longitudinally thereof, and locking dogs mounted in the body memberand projecting through andmovable longitudinally of the slots for locking the bit expanding means in the inactive. position at either limit of travel of the dog-s i-ri the slots,'.l said dogs being also movable laterally of the body member, and said dogs andbody member'having coactive means for positively locking the dogs against longitudinal movement'. at either limit of their longitudinal movement in the slots, said locking means comprising a pair of pins. on each dog spaced` longitudinally thereof, 'and pairs or' spaced recesses .in the vside Walls of the slots spaced apart corresponding to the pins,f the number of pairs of recesses ineach slot exceeding the number ofy pins in a dog by one.

' 8. In an underreamer, an elongated body member, reamer bits carried-thereby, bit

expanding means in and movable :longitudif nal of the body member in opposite directions, a spring' constraining the bit expand.- ing. means to` move inthe active direction,

'triggers carried by the body member and movable with the bit expanding'means and also laterally thereof, operating means forl the triggers carried bythe bodyvv member,

and said triggers and operating means having ooactive beveled portions for causing l lateral movement of the triggers, and longitudinally movable dogs carried bythe body membergin coactiverelation to the triggers,

said dogs 'and body member having coactive lmeans for-' locking the-dogs at either .limit of theirtravel. in coactive lrelation to the triggers...`

l 9. In an underreamer, an elongated body member, reamerbits'carried thereby, longitudin'ally movable bit expanding means in the, body member, a spring constraining' the" bitt expanding-means tomove .in the active direction, triggers mounted inland movable longitudinally of the body member`- in operative relation to the bit expanding means, each trigger having beveled shoulders, corresponding beveled shoulders in fixed relation "to the body member and in operative relation to the beveled shoulders of the triggers, and longitudinally movable dogs mounted in and extending tothe surface of the body member, said dogs being movable along the triggers lengthwise thereof, and the dogs and body member having coactive means for hplding the dogs in engagement with the triggers, and to hold the dogs against longitudinal movement at each limit oftheir travel.

10. Iii an underreamer, an elongated'body member, reamer bits carried thereby, longitudinally movable bit expanding means in the body member, a spring constraining the bitexpanding meansV to move in the active direction, triggers mounted in and movable longitudinally of the body member in 0p-.

mounted in and extending to the surface of the body member, said dogs being movable along the triggers lengthwise thereof, and the dogsand body member having coactive means for holding the dogs in engagementJ` With the triggers, and to hold the dogs against longitudinal movement at each liiiiit of theirtravel, said dogs being movable in f the .body member laterally thereof and where engaging the triggers being grooved ict to receive the latter and 4laterally expanded to limit lateral movement withV respect to the body member and the triggers being correspondingly shaped to enter the grooves of the dogs. i

1'1. Iny an underrea'mer, a body 'member with a longitudinal lbore shorter than the body member and with opposite recesses communicating with the'bore, reamer bits 1 mounted in the recesses and movable laterally with respect thereto, a bit expanding. means mounted in' the bore and movable longitudinally thereof and having an extension entering the recesses, bit expanding wedges separate from andattached to the bit expanding means, and devices vfor lockl ing the bit expanding means in the inactive A position. v

1.2. In an underreamer, an elongated body member, bits mounted thereon, Aand bit expanding means-in the body membercomprising a reciprocatory blocklvvith diametrically sepa-rated `,tingers proiecting longitudinally from one end of'theblock, and a. stem projecting from the other end oi the block'. a guide block fixed in the body member and provided with longitudinal grooves on diametrically opposite sides for receiving the lingers in straddling relation to the block, a stop member fast to the free ends'- of the fingers, a spring surrounding the fingers between the guide block and the sto member, wedge heads separate from an fast 'to the stem of the first-named block in position to enter'between the bits to expand.'

them, and means for locking the bit expand'- ing'means in the inactive position.

' 13. In an underreamer, an elongated body member, bits mounted thereon, and bit exprising a reciprocatory. block with diametrically separated, fingers projecting longi tudinally Jfrom one end of the block, landl alstemprojecting from the other end of t Je block, a guide block fixed ,in the body member Tand provided with longitudinal grooves on diametrically opposite sides'for receiving the lingers in lstraddlingrelation to thebloek, arstoplmember fastto the free ends of'the'ingers, a spring surrounding the fingers between the guide block and the stop member, wedge heads separate from and fast to the stein .ofthe irst'named block in osition to enter between .the bits to expand'- em, and means for locking. the bit expanding'means in the inactive position,

panding means infthe body member comsaid locking means comp-rising longitudinally movable triggers with the triggers and guide block. formed with lwedge-shaped portions to cause lateral, movements of the -ngers, `and dogs movable longitudinally in the body member and having ortions exposed to the surface thereof, sald dogs and triggers having coactive' portions for engagement and the dogs and body member having coactive locking mea-ns for holding the dogs at either limit of their longitudinal movement, and the dogs being' laterally A'being provided with coactive pin and socket .connections for movement of the active ends of the reaming bits thereabout.

In testimony, `that'I claim the foregoing as my own, I have hereto aiixed my slgnature in the presence oftwo witnesses.

' JOSEPHLORENZ;

l Witnesses:

ANDREW Smartm, ADoR'rHA S. CAREY. 

